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IUE and optical observations of V861 Sco.
Howarth, I. D.; Wilson, R.; Burger, M. +7 more
We present the first results of high dispersion (Δλ ≃ 0.2 Å) IUE spectra of the possible X-ray binary V 861 Sco (HD 152667) taken at several orbital phases. Contemporary optical spectroscopy, uvbyβ and infrared photometry are also reported.
The UV spectrum is quite normal for the spectral type (B0Ia), with P Cygni profiles on a number of line…A high resolution IUE spectrum of the GO-GSIA supergiant HR 8752.
Stickland, D. J.; Lambert, D. L.
A high-resolution long-wavelength IUE spectrum of the G0-G5Ia supergiant HR 8752 and its B main sequence companion is discussed. The supergiant, which dominates for wavelengths greater than approximately 2700 A, appears to have a normal spectrum. The spectrum of the B star contains several deep asymmetric absorption lines. It is argued that these …
Molecules in celestial objects. II. IUE observations of CO towards psi Per (B5 Ve).
Tarafdar, S. P.; Swamy, K. S. K.
Absorption features corresponding to 1-0, 2-0, 3-0 and 4-0 bands of the A-X transition of CO have been identified in the spectra of a hot shell star, Psi Per (B5 Ve, E(B-V)=0.09). Arguments are put forward to suggest its possible origin in the circumstellar shell.
First Ultraviolet Observations of the Optical Couterpart of the X-Ray Source 2S0114+650
Bianchi, L.
The X-Ray Source 2S0114+650 discovered by SAS-3 in 1978 has been associated with a highly reddened star showing broad Hα emission. We observed this star with the LWR spectrograph on board the I.U.E. Satellite on Sep. 1980 and Feb. 1981. An Ultraviolet flux was detected longward of the 2200 Å bump, consistent with the B0.5 spectral class…
Narrow ultraviolet absorption lines of nova CYG 1978.
Friedjung, M.
The narrow Fe II and Mn II absorption lines observed by the IUE satellite have been studied by the curve-of-growth method. Data on the line of sight column densities, including the Fe II/Mn II and the nonexcited Fe II/slightly excited Fe II ratios, have been obtained. It is shown that the line wavelength shifts and the physical characteristics of …
Interstellar abundances derived from IUE data. I. Silicon depletions toward reddened stars.
Joseph, C. L.; Snow, T. P., Jr.
Surveys of abundances for species well suited to IUE's wavelength coverage and spectral resolution are undertaken to acquire interstellar line data for a large number of stars and column densities greater than those of previous instruments. A complex set of interactive computer programs has been developed for the efficient analysis of the IUE data…
Extreme Helium Stars
Lynas-Gray, A. E.
Results of research into the nature of extreme helium stars are reviewed, covering published and unpublished work carried out over the past 20 years. Three approaches are being used to investigate the nature and evolution of extreme helium stars. Abundance analysis from model atmospheres provides information useful in interpreting the evolution of…
Cos-B X-Ray Observations of CYGNUS-X-3 - an Indications for Apsidal Motion
van der Klis, M.; Bonnet-Bidaud, J. M.
Results are presented of three ∼40 d COS-B X-ray observations of Cyg X-3. The shape of the 4.8 h light curve showed variations on all observational time scales. An ∼20 d periodicity was found in the arrival time of the minimum of the light curve, interpreted as apsidal motion of an orbit with an eccentricity of ∼0.03.
Evidence in the COS-B data for time-variable gamma-ray sources in the galactic plane
Caraveo, P. A.; Strong, A. W.; Hermsen, W. +7 more
Gamma Rays from Specific Molecular Clouds
Wolfendale, A. W.; Li, Ti-Pei; Issa, M. R. +1 more
The characteristics of specific local molecular clouds which may be visible in gamma-rays are examined. Data from the SAS II and COS B satellites are used to derive observed gamma-ray fluxes and flux limits. Conversions are made to a standard energy threshold of 100 MeV, and averages are taken. Results show that on the average, not much enhancemen…